Compressors may be used in a wide variety of industrial and residential applications to circulate refrigerant to provide a desired heating or cooling effect. For example, a compressor may be used to provide heating and/or cooling in a refrigeration system, a heat pump system, a heating, ventilation, and air conditioning (HVAC) system, or a chiller system. These types of systems can be fixed, such as at a building or residence, or can be mobile, such as in a vehicle. Vehicles include land based vehicles (e.g., trucks, cars, trains, etc.), water based vehicles (e.g., boats), air based vehicles (e.g., airplanes), and vehicles that operate over a combination of more than one of land, water, and air.
Small to mid-sized refrigerated truck systems can include eutectic plates. The eutectic plates are disposed within a box of the corresponding truck and are used to maintain an air temperature within the box and thus contents of the box below a predetermined temperature. The eutectic plates are filled with a fluid and are designed to freeze at a certain temperature. The eutectic plates can be cooled to a medium temperature (e.g., 35° F.) or a low temperature (e.g., less than or equal to 0° F.). The refrigerated truck systems typically pull down a temperature of the eutectic plates at night while the truck is parked at a depot. The refrigerated truck systems typically do not run while the truck is in service (i.e. while standing at a site or while traveling between sites). The refrigerated truck systems do not maintain box set point temperatures accurately and therefore are typically used for transporting frozen goods, not fresh goods which require tighter temperature maintenance and set point tolerances.
Some refrigerated truck systems include, in addition to the eutectic plates, a blower/evaporator (hereinafter referred to as an “evaporator”). The evaporator is run as needed and to maintain a temperature within a box of the truck while the corresponding truck is in route between sites. The evaporator is powered by a battery pack, which is charged by solar power or via an alternator and/or generator. The alternator and/or generator are driven by an engine of the truck. While the engine is running, sufficient power is available to run the alternator and/or generator and thus charge the battery pack. However, when the truck is stopped or solar panel output is low, the battery pack is not being charged and the evaporator may not be able to be operated. This inability to operate can cause excessive temperature variation within the box of the truck, which limits the usefulness of the evaporator.
The background description provided here is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.